Abstract: Virtual Observatory Data Access Service(VO-DAS) , based on the emerging technology of data grid, achieved its goal of accessing distributed and heterogeneous data resources through a uniformed way by exposing simple, practical and standardized interfaces to its clients.We designed a client system for the system, including GUI and COMMAND LINE . Users can easily access heterogeneous astronomy data through these client interfaces. This paper focuses on the design and implementation of the VO-DAS client system.